JPH11250508A - Disk centering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk centering device by which clamping force of a disk with magnetic hub is easily adjusted. SOLUTION: A position of height of a clamping member 11 on which a magnet 10 is mounted is changed without detaching the disk 4 and the clamping force of the disk 4 with the magnetic hub 3 is easily adjusted by energizing the clamping member 11 which is slidably fitted into a centering boss 9 and is fitted into a cylindrical recessed part 6 upward by a coil spring 12 and making the clamping member 11 be drawn downward at a vacuum generating source to be communicated with a hole 7 of the recessed part 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk centering device used for an inspection device or an information recording device for a disk having a magnetic hub.

[0002]

2. Description of the Related Art Information is recorded on a disk master such as an optical disk or a magnetic disk by a method such as cutting or magnetization using a laser beam or the like. Some of these disc masters have a magnetic hub around a center hole.

As shown in FIG. 3, a conventional disk centering device used for a disk inspection device and an information recording device having a magnetic hub has a clamp base 15 connected to a rotating device. A centering boss 16 is provided at the center of the upper end surface, and a cylindrical recess 1 is provided around the centering boss 16.
7, a ring-shaped clamp member 19 in which a magnet 18 is embedded is fitted to the centering boss 16 and its outer peripheral surface is screwed to the recess 17. A set screw 20 for preventing rattling of the clamp member 19 during high-speed rotation is also attached to the wall surface of the recess 17.

[0004] The disk 4 having the magnetic hub 3 is fitted with its center hole at the tip of the centering boss 16, mounted on the upper end surface of the clamp base 15, and is magnetized by the magnet 18 of the clamp member 19. Is sucked and clamped by the clamp base 15. When clamping,
The screwing position of the clamp member 19 is adjusted so that the thin disk 4 is not deformed, so that the attractive force of the magnet 18 becomes appropriate.

[0005]

In the above-mentioned conventional disk centering device, the clamp member 19 in which the magnet 18 is embedded is screwed to the concave portion 17 of the clamp base 15, so that when adjusting the clamping force, the centering device is required. Outgoing boss 16
It is necessary to temporarily remove the disk 4 fitted in the clamp member 19 and change the screwing position of the clamp member 19, which causes a problem that the working efficiency is extremely low. Further, since the clamp member 19 is fastened and fixed by the set screw 20, the clamp base 15 on which the disk 4 is placed is adjusted by adjusting the tightening force.
There is also a problem that accuracy of the upper end surface is deteriorated.

It is an object of the present invention to provide a disk centering device capable of easily adjusting the clamping force of a disk with a magnetic hub.

[0007]

In order to solve the above-mentioned problems, the present invention provides a centering boss at the center of the upper end surface of a clamp base connected to a rotating device, and a cylindrical boss around the centering boss. A ring-shaped clamp member, which is slidably fitted to the centering boss and has a magnet mounted thereon, is urged upward by an elastic member and fitted into the cylindrical concave portion. A hole communicating with a vacuum source is provided at the bottom of the plate, and means for sealing a gap between the outer peripheral surface of the clamp member and the wall surface of the concave portion is provided.

That is, the clamp member slidably fitted to the centering boss and fitted in the cylindrical concave portion is urged upward by an elastic member, and is pulled downward by a vacuum generating source communicating with the concave portion. The height of the clamp member on which the magnet is mounted can be changed without removing the disk, so that the clamping force can be adjusted.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
An embodiment of the present invention will be described.

In this disk centering device, as shown in FIG. 1, a clamp base 2 is coupled to a rotating shaft of an air spindle 1 as a rotating device, and a disk having a magnetic hub 3 on an upper end surface of the clamp base 2. 4 is clamped by magnetic force, and is rotated at high speed. On the side surface of the air spindle 1, there are provided a pipe 5 for supplying air to the bearing portion of the rotating shaft, and a pipe 8 communicating with a hole 7 provided in a concave portion 6 of the clamp base 2 described later and connected to a vacuum source. Installed.

As shown in FIG. 2A, the clamp base 2 has a cylindrical concave portion 6 formed on the upper end surface, and a centering boss 9 is set up on the bottom surface of the concave portion 6 at the center thereof. A hole 7 communicating with the pipe 8 is provided.
A ring-shaped clamp member 11 having a magnet 10 embedded therein is slidably fitted to the centering boss 9, urged upward by a coil spring 12, and fitted into the cylindrical recess 6. A retaining ring 13 that regulates the upper limit position of the clamp member 11 is also mounted on the centering boss 9.

On the outer peripheral surface of the clamp member 11, an O-ring 14 for sealing a gap between the outer peripheral surface and the wall surface of the concave portion 6 is mounted. As shown in FIG. 2B, the clamp member 11 is pulled downward.

The disk 4 with the magnetic hub 3 fitted to the tip of the centering boss 9 is attracted by the magnet 10 of the clamp member 11 and clamped on the upper end surface of the clamp base 2. By changing the position by sucking air from the hole 7, the clamping force is adjusted.

[0014]

As described above, the disk centering device of the present invention slidably fits on the centering boss and urges the clamp member fitted in the cylindrical recess upward with the elastic member. At the same time, it is pulled downward by a vacuum source communicating with the concave portion, and the height position of the clamp member on which the magnet is mounted can be changed without removing the disk, so that the clamping force of the disk with the magnetic hub can be easily reduced. Can be adjusted.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a disk centering device.

FIGS. 2a and 2b are cross-sectional views showing a main part of FIG. 1 in an enlarged manner.

FIG. 3 is an enlarged sectional view showing a main part of a conventional disk centering device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air spindle 2 Clamp base 3 Magnetic hub 4 Disk 5 Piping 6 Recess 7 Hole 8 Piping 9 Centering boss 10 Magnet 11 Clamp member 12 Coil spring 13 Retaining ring 14 O-ring 15 Clamp base 16 Centering boss 17 Recess 18 Magnet 19 Clamp Member 20 Set screw

Claims (1)

[Claims] 1. A centering boss is provided at the center of the upper end surface of a clamp base coupled to a rotating device, and a cylindrical concave portion is formed around the centering boss so as to be slidably fitted to the centering boss. And a ring-shaped clamp member on which a magnet is mounted is urged upward by an elastic member and fitted into the cylindrical concave portion, and a hole communicating with a vacuum generation source is provided at the bottom of the concave portion, A disk centering device provided with means for sealing a gap between an outer peripheral surface of the clamp member and a wall surface of the concave portion.